Transplant handling means

ABSTRACT

Process and apparatus are described for handling and treating a plurality of seeds including the method of (1) forming a continuous transplant carrier provided with spaced containers, each of sufficient size to accommodate a germinated seed or plant, and media to support growth and provided with means for exchange of moisture and gases, (2) inserting seed and support media within the containers, and (3) germinating and preculturing the seeds in the containers for at least a period of time to allow radical and cotyledon to emerge from the seed coats and develop. The invention is particularly useful in the automated transplanting of a variety of plants including high value crops such as sugar beets and lettuce.

United @tates Fatem [191 Kesinger et a1.

[11] Emma? Mar, 27, 1973 1 TRANSPLANT HANDLING WEANS [73] Assignee: TheGales Rubber Company,

Denver, C010.

[22] Filed: 30, 1970 [21] Appl. No.: 102,582

[52] US. Cl. ..47/34.13, 111/1, 47/37, 47/56 [51] Int. Cl ..A0lg 9/10,AOlc 11/02 [58] Field of Search ..47/1.2, 16, 34, 34.13, 37, 47/56, 58;111/96, 1

[56] References Cited UNITED STATES PATENTS 3 ,375,607 4/1968 Melvold..47/37 3,611,634 10/1971 Dalton ..47/34.l3 X 3,362,106 1/1968 Goldring..47/56 3,209,492 10/1965 Brandt ....47/l6 3,331,155 7/1967Chancellor..... ....47/37 3,517,629 6/1970 Bridges et a1 ..1 11/96FOREIGN PATENTS OR APPLICATIONS 1,041,133 9/1966 Great Britain ..47/56Primary Examiner-Robert E. Bagwill Attorney-Raymond Fink, H. W. Oberg,Jr. and Curtis H. Castleman, Jr.

[ ABSTRACT Process and apparatus are described for handling and treatinga plurality of seeds including the method of (1) forming a continuoustransplant carrier provided with spaced containers, each of sufficientsize to accommodate a germinated seed or plant, and media to supportgrowth and provided with means for exchange of moisture and gases, (2)inserting seed and support media within the containers, and (3)germinating and preculturing the seeds in the containers for at least aperiod of time to allow radical and cotyledon to emerge from the seedcoats and develop. The invention is particularly useful in the automatedtransplanting of a variety of plants including high value crops such assugar beets and lettuce.

7 Claims, 5 Drawing Figures PATENTEUmznm sum 1 OF 2 SFEGJZ INVENTORS. 4DONALD A. KESINGER LELAND S. NSCHO PATENTEURARZYISYZ, 3,722 l 37 SHEET 2or 2 3 'IIIIIIIIII FIG.4

INVENTGRS. DONALD A. KESINGER LELAND s. INSCHO TRANSPLANT HANDLING MEANSBACKGROUND OF THE INVENTION This invention relates to a transplanthandling means in which seedlings supported along a continuoustransplant tape are adapted to be planted in uniform spacedrelationship.

It has been the common practice in automated seed tape planting to plantindividual seeds at approximately equally spaced intervals by spacingindividual seeds along the length of two rolls of paper to form a seedtape, and then tearing off and planting at the proper location segmentsof the tape containing a single seed. The process described in US. Pat.No. 3,294,045 (Kelley) proceeds a step further beyond conventionalmethods by treating the seed tape to pregerminate all of the seedscontained in the tape prior to placement into the ground. In Kelley,pregermination is defined to -mean that the seed tape is placed in acontrolled environment for a period of time necessary to bring the seedsto the point where the roots are just ready to emerge from the seedcoat.

While continuous seed tape planting methods have seeds, the methodssuffer from a number of drawbacks which are overcome by the presentinvention. One such drawback is that seeds, as compared with seedlings,are more susceptible to certain adverse environmental conditions withinthe field. For instance, seeds are generally more affected thantransplants by insects such as root maggot and various weeds. At thesame time bare seeds are moresensitive to herbicides and insecticidesthan seedlings or transplants. Thus, in the case of seedlings ortransplants, it is possible at the time of planting to use increasedstrength post emergence herbicides rather than conventionalpre-emergence herbicides. Another advantage of using seedlings which arealready well established is that the crops will mature earlier forharvest and may grow over a longer period of time, thereby producing alarger crop that is more highly developed, e.g. in the case of sugarbeets producing a larger crop with higher sugar content per sugar beetharvested.

A further advantage of employing transplants over seeds is that thepreculturing period of the transplant provides a head start which willparticularly be advantageous in relatively cold climates such as foundin Minnesota and Colorado, where the growing season is oftentimes tooshort for a variety of crops. Other advantages of the invention includea process by which substantial uniform emergence of all seedlings isobtained so that a one-pass harvest is all that is necessary; the needfor hand or mechanical thinning is minimized; and such common emergenceproblems as soil crusting, salt accumulation, high temperature impedinggermination, poor aeration and damp-off are obviated.

Another important advantage of the present invention is the provision ofimproved transplant carrier tape constructions in which there ismaximized area for emergence and development of the seedlings throughrelatively large openings in the tape structure, and porosity isprovided in the tape containers to enhance transfer of moisture andgases to the seedlings during preculture and after planting. Stillanother advantage is realized by provision of means to maintain theposition of the ungerminated seeds and support medium in the tapecontainers during handling and transport, prior to preculture.

The most pertinent prior art known to the applicants may be found in US.Pat. Office classifications Class 47, 53, 61, and l l l. Exemplaryreferences include US. Pat. Nos. 3,172,234 to Eavis; 3,177,616 toSawyer; 3,305,968 to Dosedla et al., British Patent No. 1,030,658 andGerman Pat. specification 1,877,266.

The above enumerated advantages, inter alia, are met, and thedisadvantages of the prior art overcome by employing the process andconfiguration of the present invention.

SUMMARY OF THE INVENTION Briefly described, one aspect of the inventioncomprises a process for treating seeds including: (1) forming acontinuous transplant carrier tape having spaced containers or capsulesin which is inserted an individual seed and media to support its growth,and (2) germinating and preculturing the seeds within the capsules forat least a period of time to allow radical and cotyledon to emerge fromthe seeds and develop for a further period of time. In one embodiment ofthe invention, the continuous transplant carrier tape may comprise along flexible cover or support backing on which is affixed at spacedintervals in corrugated cardboardlike fashion a plurality of receptaclesto form capsules or containers having openings means for emergence ofthe growing plant, and aperture means to allow the exchange of moistureand gases through the capsules. The continuous transplant carrier isadapted to be fed through a planting mechanism which individually seversand plants the containers and the included plants in soil or othernutrient environment.

The method and apparatus of the invention is particularly adapted to theplanting of row crops which may be ordinarily transplanted, such assugar beets, lettuce, broccoli, cauliflower, tomatoes and cabbage.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, in which likenumerals refer to like parts in the several figures, FIG. 1 depicts apartial cutaway view of a portion of a continuous transplant carriertape prior to preculturing; FIG. la is a sectional view of FIG. 1 takenalong Section la-la; FIG. 2 is an elevational view of an alternativetransplant tape configuration shown after a portion of the preculturingperiod has elapsed; FIG. 3 is a schematic view of apparatus adapted toform the transplant tape; and FIG. 4 is a schematic side view of FIG. 3.

PREFERRED EMBODIMENTS OF THE INVENTION 14, which may be attached, forexample, by heat sealing or by use of a suitable adhesive. Thereceptacles 14 are preferably formed by furrowing or wrinkling a longpiece of suitable material and affixing valley portions to the backing.It is also preferred to taper the receptacle 14 at the bottom end 16 tofacilitate root emergence and retainment of support media 24 and seed26. This tapering procedure produces slack pleats 18 along the lowerportion of the tape carrier. The upper end 20 and lower end 22 of thecapsules are open to allow emergence of stems, leaves and roots,particularly taproots.

The contents of the capsule are preferably held in place by the use ofretaining means 28,-such as a water soluble binder. This binder alsoserves the important function of maintaining the desired position of theseeds in the capsules during handling and transport. A plurality ofperforations provide porosity in either the receptacle 14, backing 12,or both, for exchange of moisture and gases across the container wall.The final capsule arrangement takes on a corrugated cardboard or machinegun belt like configuration. An alternative capsule design is shown inthe embodiment of FIG. 2 in which seedlings 27 is shown contained withina molded plastic capsule 29 having a generally middle hemisphericalenclosure 31 to house and support the seed. This center section of thetransplant enclosure has openings 25 provided for exit of the cotyledonand radical respectively. In this embodiment, the container 29 is heatsealed to a continuous paper backing 13. The capsule preferably isprovided with openings at its end portions (not shown), althoughopenings may be provided automatically at planting by a mechanism whichpunches out the capsule and severs the container at its extremities toproduce openings at its margin. If the latter method is employed, thecapsules should be of sufficient size to accommodate the preculturedplant to avoid stunting its growth. 7

A number of types of seeds including vegetable, sugar beet and othertypes of seeds whose plants are commonly transplanted may be employed.Particularly applicable are high value row crops which may suffer fromcrowding or a short growing season, such as sugar beets, lettuce,broccoli, cauliflower, tomatoes and cabbage. For uniform emergence, itis preferred to selectively upgrade the seeds. It is preferred that ofthe seeds'utilized, at least 90 percent, more preferably at least 95percent, and most preferably at least about 99 percent germinate.Commonly employed methods of grading, exemplified by yibrationtechniques, the density-gravity table, color coding and airclassification are useful. It has been found that in general the moredense seeds produce higher germination rates. If desired, a viabilitydetection system may be employed to detect capsules having ungerminatedseeds and a method employed to selectively remove the undesiredcapsule(s) and rejoin the continuous carrier tape. A photocell could beused in such a detection system.

The receptacles 14 and backing 12 may be made of the same differentmaterial. Preferably, the materials are made of a material suitable forrolling on a spool, for instance, and adapted to be handled by amechanized planter. A variety of plastic materials including natural andsynthetic resins such as cellulose acetate, butyrates, styrenes, saran,polyethylenes, etc.,

may be utilized. The thermoplastics are preferred for both backing andreceptacle for economic reasons and since they may easily be joinedtogether by heat sealing and the desired shape maintained by vacuum.Other suitable materials include cloth, absorbent filter paper which hasits-own built-in porosity), light cardboard materials and foil. Varioustypes of packaging film may be utilized. a

The support media 24 may comprise aqueous medium, nutrient medium suchas soil or vermiculite, insecticides, fungicides, herbicides, growthregulators, fertilizers or compatible mixtures thereof. 'Various othertypes of support media such as activated charcoal for herbicideprotection, if necessary, could also be employed. The type of seeds andenvironment which the young transplant will be subjected to will dictatethe optimum composition of support media. Water soluble binder 28 isprovided as a sealant to maintain the support media and seed in thecapsule during transport, handling, etc. A plug could be supplied by awater soluble pellet which would fit snugly into the capsule.Preferably, loose support medium is placed over the seed and this mediumsprayed lightly with the water soluble binder or adhesive. Examples ofsuitable binders include starch, sugar solution, polyvinyl alcohol,polyacrylamides and cellulose derivatives such as hydroxyethylcellulose. Alternatively, the seeds could be heat sealed or glued to thewall of the container 14 or backing 12 to thereby retain the seed in itsproper position in the case handling or transport might cause excessivevibration and migration of the seed away from its initial positionwithin the capsule. Also, the backing 12 could be provided with anextended portion adapted to be folded over the opening 20 to retain thecontents of the capsule during transport, storage, etc.

2. Tape Manufacture An illustrative, non-limiting procedure formanufacturing continuous carrier transplant tape is shown in FIGS. 3 and4. Accordingly, a first roll of plastic 34 such as 1 mil thickpolyethylene is fed onto a large rotary die 36. The first stage of thisrotary die has a matching die shape 38 which forms one half of thecapsule as the roll of plastic is fed through the die. The shape andposition of the plastic is maintained by a vacuum manifold built intothe die. Alternative forming operations such as thermal forming orvacuum forming could be employed. A second sheet of plastic from rioll32 is fed through hot perforator 40 and over heat seal roller 42 to forma backing cover juxtaposed and firmly attached to the sheet of openfaced receptacles carried by the rotating die 36. l

The capsule envelope 44 formed by thelheat sealing operation is nextfilled with support media metered in from the bin 46 to approximatelyone-fourth inch depth, for example, from the top of the capsule. Theportion of support media released from the metering wheel is ejectedwith a horizontal velocity matched to coincide with the velocity of therotating die 36, allowing continuous and high speed production.

At this point in the process, the partially filled capsule receives aseed from the seed selection device comprising a seed hopper 48 and avacuum wheel pickup 50 having a plurality of fingers 52. The vacuumwheel rotates about an axis which is approximately to the horizontal.The fingers 52 pick up a single seed and are made to release the seed ata position above the partially filled capsule which is traveling by. The

vacuum wheel should be rotating at a speed necessary to supply a seedfor each capsule. it may be sometimes advantageous to provide two vacuumfingers per capsule cavity to increase the probability that a seed willbe present for each capsule. Control devices or detection systems can beutilized (such as use of a photo cell, electrostatic device or air flow)to insure that a seed is provided each capsule. One such method ofcontrol would be to use a hypodermic needle with the vacuum pick-upfinger and adjust the vacuum level according to the weight and geometryof the particular seeds. in the case where more than one seed is pickedup by the vacuum finger, a fluidic, pneumatic, electronic or othercircuit can be used to detect the extra seed(s) and cause this finger tobe bypassed in favor of a succeeding finger having a single seed.

Preferably, an additional small portion of support media is metered intothe capsules to cover the seed. This depth will vary according to thetype of seed utilized, although preferably the seed location is in theupper one-third portion of the capsule 14. At this point, it ispreferred to spray a small amount of water soluble binder to maintainthe growth medium in the capsule from spray nozzle 54. The capsules mayalso be sprayed from below, depending on whether the support medium hasa tendency to spill out the bottom. Generally this will not be necessarybecause of the tapered design of the capsule. Once the capsules havebeen sprayed, the tape is preferably wound by machine onto a large rollwhich may contain, for example, from 4,000 to 25,000 capsules. Theserolls of tape 56 may be provided with a pressure sensitive leader oneach end so that they may be positioned on a planter for automatedplantings and to prevent unrolling.

3. Germination and Preculture The next step of the process involvestransport of the transplant carrier tape to a suitable germination andpreculturing environment such as a large germination environmentchamber, or more preferably a green house. The requirements forgermination willdepend upon the particular type of seed and conditionsunder which the seed will eventually mature in the field. Optimumconditions of temperature, moisture level, aeration, light and theinteraction of these factors should be maintained to optimizegermination and overcome any germination blocks. For example, lettucemay require continuous lighting and temperatures less than 76Fahrenheit, preferably from about 59 to 65 Fahrenheit. For sugar beets,the optimum temperature will be somewhat greater than that for lettuce,generally in the range} approximately near of 65 to 85 Fahrenheit,Cooler temperatures maintained at night may help to improve fieldsurvival after transplanting.

For any particular seed to germinate, a definite amount .of water mustbe absorbed, and this moisture requirement may be provided by irrigationor subirrigation using a sprinkler system, misting or soaking.Preferably, an automatic sprinkler system would be maintained to providethe necessary moisture either continuously or at intervaled timeperiods.

The length of preculturing will be dependent upon the temperature,moisture level, lighting, particular type of seed, etc., but in generalwill extend for a period of time at least to allow radical and cotyledonto totally emerge from the seed coats. Preferably, the time periodcotyledon emerge. In general, the preculturing time period willpreferably extend for from about 10 days to about 10 weeks. As anexample, in the culturing of sugar beets, it is preferred that thepreculturing time period last for a least from about 6 to about 12weeks, more preferably from about 8 to 10 weeks. This extra length ofculturing has been found to greatly enhance the ultimate performance ofthe seedlings in the field and resultant crop production and-quality, aswell as providing improved resistance to herbicides, insecticides,frost, etc.

Once the continuous transplant carrier tape has been subjected togermination and preculturing, the transplant tapes are ready to beattached to the planter which will sever individual capsules, insertingthem into the soil one at a time at whatever spacing is desired.Preferably, upright growth attitude of the seedlings is maintainedduring planting.

4. Field Examples As an illustrative example of the advantages of thepresent invention, a 6 X 6 Latin Square was laid out on a farm in EastGrand Forks, Minnesota, and planted with hybrid sugar beet seeds andtransplants according to the present invention. Each plot measured 35feet in length and 44 inches in width. Various sizes of the sugar beetseeds including coated and unco'ated seeds were planted in a number ofthe plots. A number of transplantcapsules according to the presentinvention whichhad been precultured in a germinating environment forabout 8 to 9 weeks were also planted in certain of the plots of theLatin Square. The tape capsule construction was essentially identical tothat shown in FIG. 1, where the backing and compartment capsules weremade of 1 mil polyethylene heat sealed together.

' The support medium used in the capsules consisted of vermiculite, peatmoss, basic nutrients and trace elements. The resulting yield showedthat the transplant sugar beets according to the present inventionproduced a gross sugar increase of 16.6 weight percent greater than theyields produced from the directly seeded control sample.

A test similar to the above was carried out on the same farm using fourreplicated plots and control plots of sugar beets. The preculturingtime-period was 11 days. The transplanted sugar beets yielded a 7percent gross increase in sugar content over the control samples.

5. Modifications of the Invention It should be understood that theinvention is capable of a variety of variations and modifications whichwill be made apparent to those skilled in the art by a reading of thepresent specification. One example of such a modification is a variationof the transplant tape structure, where the backing l2 and receptacle 14are matching concave elements, i.e. mirror images, bonded together atvarious locations to form the capsules. As a further example, thebacking cover 12 could be a continuous flat sheet, carrying individuallyattached molded receptacles sealed to the backing rather than a seriesof furrows or wrinkles formed from a continuous plastic sheet.Furthermore, individual capsules could be supported on a flexiblebacking or carrier made of wire, tubing, filiament, string or othersupport. All such modifications and variations are meant to be includedwithin the scope of the present invention as defined by the appendedclaims.

We claim:

' 1. A transplant carrier comprising:

a. a flexible backing;

b. a plurality of receptacles comprising wall portions firmly attachedto said backing at a plurality of locations therealong and the combinedbacking and receptacles forming a series of spaced capsules containingtherein a germinated seed or plant and loosely packed growth media, eachindividual capsule having an upper opening foremergence of stem andleaves, and a lower opening for emergence of roots;

. aperture means in either or both of said backing .and walls of saidreceptacle of sufficient size for providing exchange of moisture andgases, yet said size of the aperture means being sufiiciently small toretain substantially all of the growth media within the capsules; v saidwall portions of the receptaclecomprising an .upper and a lower portion,said lower portion tapering and funneling downwardly to said loweropening for facilitating root growth and emergence; and

d. means within said receptacle retaining said growth media in relativeposition within the capsule.

2. The carrier of claim 1 wherein the backing and receptacles are formedof sheets of plastic material.

3. The carrier of claim 2 wherein the shape of the backing andreceptacles are essentially the same, and the two are bonded back toback at spaced locations to form a continuous tape having spacedcontainers.

4. The carrier of claim 1 formed in a manner substantially resembling acorrugated configuration.

5. The carrier of claim 1 wherein a water soluble binder is incorporatedinto the capsule contents at either or both of its said openings toprovide said retaining means.

6. The carrier of claim 1 wherein the aperture means include aperturesuniformly distributed substantially throughout the walls of saidreceptacle, backing member or both.

. 7. The carrier of claim 1 wherein said wall portion of the receptacleadditionally contains a generallyhem ispherical middle portion housingand retaining said germinated seed.

1. A transplant carrier comprising: a. a flexible backing; b. aplurality of receptacles comprising wall portions firmly attached tosaid backing at a plurality of locations therealong and the combinedbacking and receptacles forming a series of spaced capsules containingtherein a germinated seed or plant and loosely packed growth media, eachindividual capsule having an upper opening for emergence of stem andleaves, and a lower opening for emergence of roots; c. aperture means ineither or both of said backing and walls of said receptacle ofsufficient size for providing exchange of moisture and gases, yet saidsize of the aperture means being sufficiently small to retainsubstantially all of the growth media within the capsules; said wallportions of the receptacle comprising an upper and a lower portion, saidlower portion tapering and funneling downwardly to said lower openingfor facilitating root growth and emergence; and d. means within saidreceptacle retaining said growth media in relative position within thecapsule.
 2. The carrier of claim 1 wherein the backing and receptaclesare formed of sheets of plastic material.
 3. The carrier of claim 2wherein the shape of the backing and receptacles are essentially thesame, and the two are bonded back to back at spaced locations to form acontinuous tape having spaced containers.
 4. The carrier of claim 1formed in a manner substantially resembling a corrugated configuration.5. The carrier of claim 1 wherein a water soluble binder is incorporatedinto the capsule contents at either or both of its said openings toprovide said retaining means.
 6. The carrier of claim 1 wherein theaperture means include apertures uniformly distributed substantiallythroughout the walls of said receptacle, backing member or both.
 7. Thecarrier of claim 1 wherein said wall portion of the receptacleadditionally contains a generally hemispherical middle portion housingand retaining said germinated seed.